/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.yiguantong.police.qrCode.utils.view;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.NinePatch;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.util.AttributeSet;
import android.view.View;

import com.yiguantong.police.R;
import com.google.zxing.ResultPoint;
import com.yiguantong.police.qrCode.utils.camera.CameraManager;

import java.util.Collection;
import java.util.HashSet;


/**
 * This view is overlaid on top of the camera preview. It adds the viewfinder
 * rectangle and partial transparency outside it, as well as the laser scanner
 * animation and result points.
 * 
 * @author dswitkin@google.com (Daniel Switkin)
 */
public final class ViewfinderView extends View
{
    
    /**
     * 刷新界面的时间
     */
    private static final long ANIMATION_DELAY = 10L;
    
    private static final int OPAQUE = 0xFF;
    
    
    /**
     * 中间那条线每次刷新移动的距离
     */
    private static final int SPEEN_DISTANCE = 5;
    
    /**
     * 画笔对象的引用
     */
    private Paint paint;
    
    /**
     * 中间滑动线的最顶端位置
     */
    private int slideTop;
    
    /**
     * 将扫描的二维码拍下来，这里没有这个功能，暂时不考虑
     */
    private Bitmap resultBitmap;
    
    private final int maskColor;
    
    private final int resultColor;
    
    private final int resultPointColor;
    
    private Collection<ResultPoint> possibleResultPoints;
    
    private Collection<ResultPoint> lastPossibleResultPoints;
    
    boolean isFirst;
    
    private NinePatch np;
    
    public ViewfinderView(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        
        paint = new Paint();
        Resources resources = getResources();
        maskColor = resources.getColor(R.color.viewfinder_mask);
        resultColor = resources.getColor(R.color.viewfinder_laser);
        resultPointColor = resources.getColor(R.color.possible_result_points);
        possibleResultPoints = new HashSet<ResultPoint>(5);
    }
    
    @Override
    public void onDraw(Canvas canvas)
    {
        //中间的扫描框，你要修改扫描框的大小，去CameraManager里面修改
        Rect frame = CameraManager.get().getFramingRect();
        if (frame == null)
        {
            return;
        }
        //初始化中间线滑动的最上边和最下边
        if (!isFirst)
        {
            isFirst = true;
            slideTop = frame.top;
        }
        //获取屏幕的宽和高
        int width = canvas.getWidth();
        int height = canvas.getHeight();
        
        paint.setColor(resultBitmap != null ? resultColor : maskColor);
        
        //画出扫描框外面的阴影部分，共四个部分，扫描框的上面到屏幕上面，扫描框的下面到屏幕下面
        //扫描框的左边面到屏幕左边，扫描框的右边到屏幕右边
        canvas.drawRect(0, 0, width, frame.top, paint);
        canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
        canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);
        canvas.drawRect(0, frame.bottom + 1, width, height, paint);
        
        if (resultBitmap != null)
        {
            // Draw the opaque result bitmap over the scanning rectangle
            paint.setAlpha(OPAQUE);
            canvas.drawBitmap(resultBitmap, frame.left, frame.top, paint);
        }
        else
        {
            //画扫描框边上的角和线,用.9png
            Bitmap bmp_9path = BitmapFactory.decodeResource(getResources(), R.drawable.capture_frame);
            // canvas.drawBitmap(bmp_9path, null, frame, paint);
            np = new NinePatch(bmp_9path, bmp_9path.getNinePatchChunk(), null);
            np.draw(canvas, frame);
            //绘制中间的线,每次刷新界面，中间的线往下移动SPEEN_DISTANCE
            slideTop += SPEEN_DISTANCE;
            if (slideTop >= frame.bottom)
            {
                slideTop = frame.top;
            }
            Rect lineRect = new Rect();
            lineRect.left = frame.left;
            lineRect.right = frame.right;
            lineRect.top = slideTop;
            lineRect.bottom = slideTop + 18;
            canvas.drawBitmap(((BitmapDrawable)(getResources().getDrawable(R.drawable.scan_line))).getBitmap(),
                null,
                lineRect,
                paint);
            //画黄色的点
            Collection<ResultPoint> currentPossible = possibleResultPoints;
            Collection<ResultPoint> currentLast = lastPossibleResultPoints;
            if (currentPossible.isEmpty())
            {
                lastPossibleResultPoints = null;
            }
            else
            {
                possibleResultPoints = new HashSet<ResultPoint>(5);
                lastPossibleResultPoints = currentPossible;
                paint.setAlpha(OPAQUE);
                paint.setColor(resultPointColor);
                for (ResultPoint point : currentPossible)
                {
                    canvas.drawCircle(frame.left + point.getX(), frame.top + point.getY(), 6.0f, paint);
                }
            }
            if (currentLast != null)
            {
                paint.setAlpha(OPAQUE / 2);
                paint.setColor(resultPointColor);
                for (ResultPoint point : currentLast)
                {
                    canvas.drawCircle(frame.left + point.getX(), frame.top + point.getY(), 3.0f, paint);
                }
            }
            
            //只刷新扫描框的内容，其他地方不刷新
            postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top, frame.right, frame.bottom);
        }
    }
    
    public void drawViewfinder()
    {
        resultBitmap = null;
        invalidate();
    }
    
    /**
     * Draw a bitmap with the result points highlighted instead of the live
     * scanning display.
     * 
     * @param barcode
     *            An image of the decoded barcode.
     */
    public void drawResultBitmap(Bitmap barcode)
    {
        resultBitmap = barcode;
        invalidate();
    }
    
    public void addPossibleResultPoint(ResultPoint point)
    {
        possibleResultPoints.add(point);
    }
    
}
